Wheeled vehicles commonly rotate one or more steered wheels about a vertical axis to turn the vehicle in a turn circle. When a steered wheel is at its rotational limit, the vehicle turns in its smallest turn circle. Factors influencing the size of a vehicle's smallest turn circle are the length of the wheelbase, that is, how far the steered wheel is located from other wheels supporting the vehicle, and the extent of rotation of the steered wheel about the vertical axis. An exemplary vehicle, such as a pallet jack 5 (FIG. 1), may have a steered wheel 10 capable of rotating 90° from a straight position to cause the pallet jack 5 to turn about a pivot 15 created by and located between the rear wheels 20 during turning maneuvers. Rotating the steered wheel 10 by 90° can result in a smallest turn circle 25 for the pallet jack 5 having a diameter that is roughly twice the vehicle wheelbase (FIG. 2), that is, the distance between steered wheel 10 and the rear wheels 20.
Some devices attempt to decrease the size of the minimum turn circle of a vehicle, such as the pallet jack 5, by providing a structure located between steered wheels and rear wheels that contacts the ground when the forks 30 are at a lowered position. For example, see the devices described in U.S. Pat. Nos. 2,598,151; 4,615,533; 5,354,080; 7,226,060; and 8,336,913.